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Demographic Profiles, Clinical Characteristics, and Meteorological Context of Heat-Related Illnesses among Hajj

Ghadah Alsaleh1, Majed Alsalamah2,3,4, Fahad Alamri1

  • 1Global Centre for Mass Gatherings Medicine, Ministry of Health, Riyadh, Kingdom of Saudi Arabia.

Saudi Medical Journal
|June 4, 2026
PubMed

Insights

Heat-related illnesses affected 1,129 Hajj pilgrims in 2023, with heat exhaustion and heatstroke being most common. Older adults and Egyptians were disproportionately affected, highlighting the need for heat-protective strategies during the Hajj pilgrimage.

Area of Science:

  • Public Health
  • Environmental Health
  • Epidemiology

Background:

  • Mass gatherings like the Hajj pilgrimage present unique public health challenges, particularly concerning environmental exposures.
  • Rising global temperatures due to climate change exacerbate the risk of heat-related illnesses (HRIs) in vulnerable populations.

Purpose of the Study:

  • To characterize the demographic profiles, clinical presentations, and meteorological conditions associated with HRIs among Hajj pilgrims in 2023.
  • To identify risk factors and inform targeted interventions for preventing HRIs during mass gatherings.

Main Methods:

  • A retrospective cross-sectional study analyzed data from 1,129 pilgrims diagnosed with HRIs.
  • Data sources included the Hajj Health Information System for pilgrim demographics and clinical data, and the National Center for Meteorology for environmental data.
  • Key meteorological factors such as temperature, humidity, wind speed, and rainfall were recorded.

Main Results:

  • Heat exhaustion (48.2%) and heatstroke (37.4%) were the predominant HRIs, with 24.9% of cases requiring hospitalization.
  • Males (55.4%) and pilgrims aged 55-74 years (64.2% of severe cases) were significantly affected.
  • Egyptians showed a disproportionate burden (32.2% of cases). High temperatures (up to 44°C) with low humidity (14%) were recorded during the Day of Arafah.

Conclusions:

  • The study highlights the significant risk of HRIs among Hajj pilgrims, particularly older adults and specific nationalities, under extreme weather conditions.
  • Urgent need for targeted interventions like heat-adaptive rituals, real-time environmental monitoring, and age-specific cooling strategies is emphasized.
  • Findings provide a crucial benchmark for managing mass gatherings in increasingly warming environments and mitigating climate change impacts.
Abstract

Keywords:
Climate changeHeat stress disordersHot temperatureMass gatheringsPilgrimageSaudi Arabia

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